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EP1847157A1 - Method for inductive heating of a workpiece - Google Patents

Method for inductive heating of a workpiece

Info

Publication number
EP1847157A1
EP1847157A1 EP06849391A EP06849391A EP1847157A1 EP 1847157 A1 EP1847157 A1 EP 1847157A1 EP 06849391 A EP06849391 A EP 06849391A EP 06849391 A EP06849391 A EP 06849391A EP 1847157 A1 EP1847157 A1 EP 1847157A1
Authority
EP
European Patent Office
Prior art keywords
axis
magnetic field
workpiece
rotation
coil
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP06849391A
Other languages
German (de)
French (fr)
Inventor
Jan Wiezoreck
Carsten BÜHRER
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BL Chemie GmbH and Co KG
Original Assignee
Zenergy Power GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zenergy Power GmbH filed Critical Zenergy Power GmbH
Publication of EP1847157A1 publication Critical patent/EP1847157A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/02—Induction heating
    • H05B6/10—Induction heating apparatus, other than furnaces, for specific applications
    • H05B6/101—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces
    • H05B6/102—Induction heating apparatus, other than furnaces, for specific applications for local heating of metal pieces the metal pieces being rotated while induction heated
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B6/00—Heating by electric, magnetic or electromagnetic fields
    • H05B6/02—Induction heating

Definitions

  • the invention relates to a method for inductively heating an electrically conductive workpiece by rotating the workpiece in the magnetic field of a superconducting windings comprising DC-conducting coil arrangement about an axis of rotation which forms an angle with the main axis of the magnetic field.
  • the flux density of the magnetic field passing through the workpiece is set differently along the axis of rotation.
  • the workpiece may in particular be a block or billet, for example of aluminum, copper or corresponding alloys. Usual diameters are between 50 mm and 400 mm, usual lengths between 20mm and 1,000 mm.
  • the axis of rotation of the workpiece makes an angle with the major axis of the magnetic field of 90 °. According to the known law of induction, the temperature increase per unit of time is greater, the higher the flux density of the magnetic field and the higher the speed of the workpiece.
  • an alternating field generating coil arrangement block is for this purpose by uniform heating to a basic temperature is additionally cost-intensive by switching on partial coils in the desired regions, which is cost-intensive, inter alia because of the ohmic losses in the coil arrangement and the control engineering effort.
  • a method for inductive heating of an electrical workpiece in the interior of an AC-powered induction coil is known, which in turn is surrounded by at least one electrical shorting ring.
  • the diameter of the short-circuit ring By changing the diameter of the short-circuit ring, its reactive power consumption can be regulated in order to achieve a steady, localized change in the specific heating power of the induction coil.
  • the invention has for its object to provide a technical realization of this method, so that the temperature of the usually cylindrical workpiece along its coincident with the axis of rotation center axis a desired course, ie a non-zero, however does not necessarily have constant temperature gradient.
  • the flux density of the magnetic field passing through the workpiece is adjusted differently along the axis of rotation. This can be done either by targeted influencing of the local flux density and / or by suitable positioning of the rotating workpiece relative to the always inhomogeneous magnetic field.
  • areas of lower flux density are referred to as (relatively) weaker magnetic fields, and conversely, areas of higher flux density are referred to as (relatively) stronger magnetic fields.
  • the magnetic field generating coil arrangement is preferably high-temperature superconducting. It can in particular consist of one or more, in the latter case mechanically parallel to each other, an approximately oval space enclosing and a dipole magnetic field generating coils, so-called race-track coils exist.
  • the workpiece rotates about an axis of rotation approximately coincident with the long axis of the oval.
  • a specifically different flux density along the axis of rotation can be generated, for example, by means of a magnetic short circuit introduced into a partial region of the magnetic field.
  • the magnetic short circuit may consist of a ferromagnetic body. Near this body, the magnetic field is weaker. The area of the workpiece lying in this magnetic field is accordingly heated to a lesser extent.
  • the different flux density along the axis of rotation can also be generated by means of an additional coil.
  • This auxiliary coil may e.g. be positioned parallel axis offset from the superconducting coil assembly.
  • the auxiliary coil may e.g. be positioned laterally adjacent to the coil assembly in the amount of one or the other end of the oval space in order to reinforce the already stronger in this area anyway stronger magnetic field. The part of the rotating workpiece located in this area is then heated more strongly.
  • Another possibility is to position the additional coil coaxially with the axis of rotation and concentrically surrounding the workpiece in a partial region of the magnetic field.
  • the workpiece is then penetrated both by the magnetic field of the coil arrangement and by the orthogonal magnetic field of the auxiliary coil fed in this case.
  • a location-dependent different flux density can also be generated by means of a ferromagnetic yoke surrounding the coil arrangement outside.
  • the yoke also has the advantage of shielding the magnetic field of the coil assembly to the outside and the same Amperewindungsiere to increase the flux density in the space enclosed by the coil arrangement and thus by the workpiece.
  • the yoke may be similar to a torus open on the inside.
  • the yoke may also have a closed or open ring or C-section with at least one pole piece on each side of the axis of rotation.
  • an open cross-section at right angles to the axis of rotation
  • the axis of rotation of the workpiece lies between the surfaces of the hollow cylinder defining the slot-shaped opening and forming the pole shoes or designed as pole shoes.
  • the coil arrangement can sit on the yoke at any desired location.
  • the magnetic field can also be generated by means of a respective superconducting coil on each shoe as a coil arrangement.
  • the flux density which differs along the axis of rotation can also be generated by a spacing of the pole faces of the pole shoes of the yoke which changes along the axis of rotation.
  • a flux density of the magnetic field passing through the workpiece along the axis of rotation can in particular also be adjusted by changing the angle enclosed by the axis of rotation of the workpiece and the main axis of the magnetic field. This angle then deviates from 90 °.
  • the point at which the axis of rotation is tilted against the main axis of the magnetic field can be selected as a function of the temperature distribution required over the length of the workpiece. If, for example, the axis of rotation is tilted about a point lying in the region of an end face of a cylindrical workpiece, then This area of the workpiece remains in the area of the strong magnetic field, while the opposite end area is in a weaker magnetic field and therefore less heated.
  • the tilt angle may be between about 2 ° and about 20 °, corresponding to an angle between about 88 ° and 70 ° included by the axis of rotation and the major axis of the magnetic field.
  • FIG. 6b the same coil arrangement as in Fig. 6a, but with tilted axis of rotation of the workpiece
  • FIG. 7a a superconducting coil on a leg of a C-shaped yoke in an end view and a partially cut and rotated by 90 ° view
  • 7b is an end view of a C-shaped yoke with an arrangement of two superconducting coils
  • FIG. 8a shows a race-track coil similar to FIG. 1, but with the axis of rotation of the workpiece tilted, FIG.
  • FIG. 9 shows a race-track coil as in FIG. 1, but with a workpiece displaced linearly along its axis of rotation in the coil interior, FIG.
  • 10b shows the same workpiece with an axis of rotation tilted by 6 ° with respect to an axis orthogonal to the axis of a magnetic field
  • Fig. 11 is a simplified, but perspective view of a cylindrical workpiece whose longitudinal and rotational axis is tilted relative to the plane of an immediate race-track coil.
  • Fig. 1 shows a superconducting race-track coil S in a schematic simplification. It includes a number of turns, not shown, and is DC-flowed to produce a dipole magnetic field. This penetrates a cylindrical workpiece W made of an electrically conductive material.
  • the workpiece may be, for example, an aluminum ingot or billet.
  • the workpiece W is rotationally driven about its longitudinal axis D. The drive is not shown. In this way, the workpiece W, as known, is heated inductively.
  • a magnetic short circuit K is located in the upper part of the oval space, here in the form of a short cylinder made of a ferromagnetic material. In the vicinity of this short circuit K, the magnetic field B passing through the workpiece W is weakened. The upper end region of the workpiece W therefore experiences less heating than those regions of the workpiece which are penetrated by the unattenuated magnetic field of the coil S.
  • Fig. 2 shows the principle the same arrangement as Fig. 1, but is offset parallel axis offset from the coil S, an additional coil Z is arranged, whose turns are also flowed through DC.
  • the additional coil Z With the same winding sense of the additional coil Z and the coil S, the magnetic fields in the sense of a reinforcement of the upper part of the workpiece W passing through total magnetic field overlap. This part of the workpiece W is therefore heated more than the rest of the part. If another area of the workpiece W is to be heated more strongly than the remaining areas, then the additional coil Z is displaced in the direction of the double arrow to the desired location.
  • the desired temperature difference or temperature increase can be set by changing the excitation current of the additional coil Z.
  • a closed yoke J can, as shown in FIG be arranged upper short leg of the coil S.
  • the yoke J improves the magnetic short circuit and simultaneously shields the magnetic field of the coil S at this point to the outside. Accordingly, in this embodiment as well, the upper region of the workpiece W is heated less than the remaining region.
  • FIG. A yoke Jl surrounds the entire Spulenan- order and thus largely shields the magnetic field to the outside.
  • the excitation power needed to generate the magnetic field with the flow direction B decreases, more specifically the excitation current through the coil S.
  • the differential heating of the workpiece W i. a temperature gradient along its axis, can also be achieved in this Anorndung with the explained with reference to Figures 1 to 3 measures.
  • FIG. 6a The arrangement shown in FIG. 6a is based on a closed yoke J2 with pole shoes P1 and P2, each of which carries a superconducting coil S1 or S2, which are electrically connected in series and through which DC flows.
  • the different strength of the magnetic field is indicated by the line width of the arrows symbolizing the field lines.
  • FIG. 6b shows a similar arrangement to FIG. 6a, but in this case the workpiece W is not achieved by displacement along the axis of rotation D but by a tilting of this axis of rotation with respect to the long axis of the coil arrangement S1, S2, J. This is due to the semi-perspective shown in the end view of Fig. 6b.
  • Fig. 7a shows an arrangement in which a superconducting coil S3 encloses the long leg of a C-shaped yoke J3, between which pole pieces P3 and P4 the workpiece rotates.
  • the cut and rotated plan view illustrates that the pole shoes P3 and P4 delimit a space wedge-shaped from right to left around the workpiece W, so that the workpiece W progressively heats progressively from right to left in accordance with the decreasing air gap.
  • This arrangement has the advantage of an over the length of the workpiece approximately constant temperature gradient.
  • FIG. 7b operates, with the only difference that instead of a coil here two superconducting coils S4 and S5 are used, each of which surrounds a pole piece P5 and P6.
  • Fig. 8a operates with a race-track coil S analogous to FIG. 1, but the different heating of the workpiece W along its axis of rotation D is achieved in that this axis of rotation relative to the median plane of the coil S by an angle ⁇ to a point lying on the central axis M is tilted.
  • the flux density B decreases from the lower to the upper end of the workpiece W, so that the upper end of the workpiece is heated less than the remaining portion thereof.
  • FIG. 8b operates, however, with two coaxially adjacent or behind one another, superconducting coils S6 and S7, whereby a higher flux density B is achieved.
  • FIG. 9 also shows a race-track coil S which carries the work W encloses.
  • the workpiece is shifted from its symmetrical position in the space enclosed by the coil S space along the axis of rotation D upwards.
  • the upper part of the workpiece W is in a region of higher flux density B than the rest of the workpiece, so it is heated more.
  • the workpiece can, if desired, additionally be tilted out of the median plane of the coil S by a point expediently located in the region of the upper end face (not shown).
  • the following table illustrates on a numerical example the achievable temperatures and temperature differences.
  • the workpiece consists of a billet with a length of 800mm and a diameter of 250mm.
  • “compensation” denotes a waiting time after completion of the inductive heating and before determination of the temperatures at the points shown in FIG. 10a.
  • the tilt angle o; in the first column is defined as in Figs. 8a and 10b.
  • the linear displacement in the second column refers to the displacement along the axis of rotation D of the workpiece explained with reference to FIG. 9.
  • the entries in the last five lines show that it may be advantageous to apply the two fundamentally separately applicable measures of displacement of the workpiece and the tilting of the axis of rotation combined.
  • Figure 11 illustrates in perspective but schematically simplified a billet with tilted axis of rotation in a race-track coil.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Induction Heating (AREA)
  • Containers, Films, And Cooling For Superconductive Devices (AREA)

Abstract

A method for inductive heating of an electrically conductive workpiece by rotating the workpiece in the magnetic field of a coil arrangement, which is formed from superconducting turns and through which direct-current flows, about a rotation axis which includes an angle with the major axis of the magnetic field, makes it possible to maintain a temperature, which differs along the workpiece, when the flux density of the magnetic field passing through the workpiece is set differently along the rotation axis.

Description

Verfahren zum induktiven Erwärmen eines Werkstücks Method for inductive heating of a workpiece
Die Erfindung betrifft ein Verfahren zum induktiven Erwär- men eines elektrisch leitenden Werkstücks durch Drehen des Werkstücks im Magnetfeld einer supraleitende Windungen umfassenden, gleichstromdurchflossenen Spulenanordnung um eine Drehachse, die mit der Hauptachse des Magnetfeldes einen Winkel einschließt. Die Flußdichte des das Werkstück durchsetzenden Magnetfeldes wird längs der Drehachse unterschiedlich eingestellt.The invention relates to a method for inductively heating an electrically conductive workpiece by rotating the workpiece in the magnetic field of a superconducting windings comprising DC-conducting coil arrangement about an axis of rotation which forms an angle with the main axis of the magnetic field. The flux density of the magnetic field passing through the workpiece is set differently along the axis of rotation.
■ Ein derartiges Verfahren ist aus „Temperature distribution in aluminum billets heated by rotation in static magnetic field produced by superconducting magnets" (Vorabdruck ■ Such a method is known from "Temperature distribution in aluminum billets heated by rotation in static magnetic field produced by superconducting magnets" (preprint
COMPEL Vol. 24, No. 1, S. 281 - S. 290, (2004)) bekannt. Das Dokument zeigt jedoch nicht auf, wie das Verfahren technisch realisiert werden kann.COMPEL Vol. 24, no. 1, p. 281 - p. 290, (2004)). However, the document does not show how the method can be technically realized.
Aus der WO 2004/066681 Al ist bekannt ein Werkstück imFrom WO 2004/066681 Al a workpiece is known in the
Magnetfeld einer gleichstromdurchflossenen Spulenanordnung zu drehen. Dies ermöglicht eine gleichmässige induktive Erwärmung des Werkstück in einem statischen Magnetfeld. Letztgenanntes wird verlustarm mittels einer hochtempera- tursupraleitenden Spulenanordnung erzeugt. Das Werkstück kann insbesondere ein Block oder Billet z.B. aus Aluminium, Kupfer oder entsprechenden Legierungen sein. Übliche Durchmesser liegen zwischen 50 mm und 400 mm, übliche Längen zwischen 20mm und 1.000 mm. Die Drehachse des Werkstücks schließt mit der Hauptachse des Magnetfeldes einen Winkel von 90° ein. Nach dem bekannten Induktionsgesetz ist der Temperaturanstieg je Zeiteinheit umso größer, je höher die Flussdichte des Magnetfeldes und je höher die Drehzahl des Werkstücks ist .To rotate magnetic field of a DC coil assembly. This allows a uniform inductive heating of the workpiece in a static magnetic field. The latter is produced with low loss by means of a high-temperature superconducting coil arrangement. The workpiece may in particular be a block or billet, for example of aluminum, copper or corresponding alloys. Usual diameters are between 50 mm and 400 mm, usual lengths between 20mm and 1,000 mm. The axis of rotation of the workpiece makes an angle with the major axis of the magnetic field of 90 °. According to the known law of induction, the temperature increase per unit of time is greater, the higher the flux density of the magnetic field and the higher the speed of the workpiece.
Aus „Strangpressen", Aluminium-Verlag Düsseldorf, 2001, 553 bis 555, ist es bekannt, einen Block induktiv so zu erwärmen, dass er in axialer Richtung ein Temperaturprofil hat, das in einer nachfolgenden Umformzone zu einer über die Länge des Blocks gleichen, optimalen Temperatur führt. Bei Leichtmetallen soll deshalb der Blockanfang oder Blockkopf eine z.B. bis zu 1000C höhere Temperatur als das Blockende haben. Bei Kupferlegierungen ist häufig die umgekehrte Temperaturverteilung erwünscht. Der linear durch eine langgestreckte, ein Wechselfeld erzeugende Spulenanordnung bewegte Block wird hierzu nach gleichmäßiger Auf- heizung auf eine Grundtemperatur durch Anschalten von Teilspulen in den gewünschten Bereichen zusätzlich erwärmt. Dieses Verfahren ist u.a. wegen der ohmschen Verluste in der Spulenanordnung und des regelungstechnischen Aufwandes kostenintensiv.From "extruding", aluminum-Verlag Dusseldorf, 2001, 553-555, it is known to inductively heat a block so that it has a temperature profile in the axial direction, which in a subsequent forming zone to one over the length of the block, optimum temperature will result. In light metals, therefore, is to the beginning of the block or block header have eg as the block end up higher to 100 0 C temperature. In the case of copper alloys, the inverse temperature distribution is often desirable. the linearly moved by an elongate, an alternating field generating coil arrangement block is for this purpose by uniform heating to a basic temperature is additionally cost-intensive by switching on partial coils in the desired regions, which is cost-intensive, inter alia because of the ohmic losses in the coil arrangement and the control engineering effort.
Aus der DE 1 215 276 A ist ein Verfahren zum induktiven Erwärmen eines elektrischen Werkstücks im Inneren einer wechselstromgespeisten Induktionsspule bekannt, die ihrerseits von mindestens einem elektrischen Kurzschlussring umgeben ist. Durch Veränderung des Durchmessers des Kurz- schlussrings kann dessen Blind- oder Wirkleistungsaufnahme geregelt werden, um eine stetige, örtlich begrenzte Veränderung der spezifischen Heizleistung der Induktionsspule zu erzielen. Ausgehend von dem Verfahren der einleitend angegebenen Gattung liegt der Erfindung die Aufgabe zugrunde, eine technische Realisierung dieses Verfahrens anzugeben, so dass die Temperatur des in der Regel zylinderischen Werkstücks längs seiner mit der Drehachse zusammenfallenden Mittelachse einen gewünschten Verlauf, d.h. einen von Null verschiedenen, jedoch nicht notwendigerweise konstanten Temperaturgradienten hat.From DE 1 215 276 A, a method for inductive heating of an electrical workpiece in the interior of an AC-powered induction coil is known, which in turn is surrounded by at least one electrical shorting ring. By changing the diameter of the short-circuit ring, its reactive power consumption can be regulated in order to achieve a steady, localized change in the specific heating power of the induction coil. Starting from the method of the introductory given genus, the invention has for its object to provide a technical realization of this method, so that the temperature of the usually cylindrical workpiece along its coincident with the axis of rotation center axis a desired course, ie a non-zero, however does not necessarily have constant temperature gradient.
Die Flussdichte des das Werkstück durchsetzenden Magnetfeldes wird längs der Drehachse unterschiedlich eingestellt. Dies kann entweder durch gezielte Beeinflussung der örtlichen Flussdichte oder/und durch geeignete Positionierung des sich drehenden Werkstück relativ zu dem stets inhomogenen Magnetfeld geschehen.The flux density of the magnetic field passing through the workpiece is adjusted differently along the axis of rotation. This can be done either by targeted influencing of the local flux density and / or by suitable positioning of the rotating workpiece relative to the always inhomogeneous magnetic field.
Im Folgenden werden der Einfachheit halber Bereiche gerin- gerer Flussdichte als (relativ) schwächeres Magnetfeld und umgekehrt Bereiche höherer Flussdichte als (relativ) stärkeres Magnetfeld bezeichnet.Hereinafter, for the sake of simplicity, areas of lower flux density are referred to as (relatively) weaker magnetic fields, and conversely, areas of higher flux density are referred to as (relatively) stronger magnetic fields.
Die das Magnetfeld erzeugende Spulenanordnung ist bevor- zugt hochtemperatursupraleitend. Sie kann insbesondere aus einer oder mehreren, im letzteren Fall mechanisch parallel nebeneinander angeordneten, einen etwa ovalen Raum umschließenden und ein Dipolmagnetfeld erzeugenden Spulen, sog. race-track-Spulen, bestehen. In diesem Raum dreht sich das Werkstück um eine mit der langen Achse des Ovals etwa zusammenfallende Drehachse. Eine längs der Drehachse gezielt unterschiedliche Flussdichte kann z.B. mittels eines in einen Teilbereich des Magnetfeldes eingebrachten magnetischen Kurzschlusses erzeugt werden. Der magnetische Kurzschluß kann aus einem ferromagnetischen Körper bestehen. In der Nähe dieses Körpers ist das Magnetfeld schwächer. Der in diesem Magnetfeld liegende Bereich des Werkstücks wird dementsprechend schwächer erwärmt .The magnetic field generating coil arrangement is preferably high-temperature superconducting. It can in particular consist of one or more, in the latter case mechanically parallel to each other, an approximately oval space enclosing and a dipole magnetic field generating coils, so-called race-track coils exist. In this room, the workpiece rotates about an axis of rotation approximately coincident with the long axis of the oval. A specifically different flux density along the axis of rotation can be generated, for example, by means of a magnetic short circuit introduced into a partial region of the magnetic field. The magnetic short circuit may consist of a ferromagnetic body. Near this body, the magnetic field is weaker. The area of the workpiece lying in this magnetic field is accordingly heated to a lesser extent.
Die längs der Drehachse unterschiedliche Flussdichte kann auch mittels einer Zusatzspule erzeugt werden.The different flux density along the axis of rotation can also be generated by means of an additional coil.
Diese Zusatzspule kann z.B. parallelachsig versetzt zu der supraleitenden Spulenanordnung positioniert werden. Die Zusatzspule kann z.B. in Höhe des einen oder des anderen Endes des ovalen Raums seitlich an die Spulenanordnung angrenzend positioniert werden um das in diesem Bereich ohnehin stärkere Magnetfeld nochmals zu verstärken. Der sich in diesem Bereich befindende Teil des sich drehenden Werkstücks wird dann stärker erwärmt.This auxiliary coil may e.g. be positioned parallel axis offset from the superconducting coil assembly. The auxiliary coil may e.g. be positioned laterally adjacent to the coil assembly in the amount of one or the other end of the oval space in order to reinforce the already stronger in this area anyway stronger magnetic field. The part of the rotating workpiece located in this area is then heated more strongly.
Eine andere Möglichkeit besteht darin, die Zusatzspule gleichachsig zu der Drehachse und das Werkstück konzentrisch umgebend in einem Teilbereich des Magnetfeldes zu positionieren. Das Werkstück wird dann sowohl von dem Magnetfeld der Spulenanordnung als auch von dem dazu orthogonalen Magnetfeld der in diesem Fall wechselstromgespeisten Zusatzspule durchsetzt.Another possibility is to position the additional coil coaxially with the axis of rotation and concentrically surrounding the workpiece in a partial region of the magnetic field. The workpiece is then penetrated both by the magnetic field of the coil arrangement and by the orthogonal magnetic field of the auxiliary coil fed in this case.
Eine ortsabhängig unterschiedliche Flussdichte kann auch mittels eines die Spulenanordnung aussen umgebenden, fer- romagnetisehen Jochs erzeugt werden. Durch entsprechende Gestaltung der Geometrie des Jochs längs der geraden, langen Spulenseiten lässt sich die Stärke des Magnetfeldes längs der Drehachse beeinflussen. Das Joch hat gleichzeitig den Vorteil, das Magnetfeld der Spulenanordnung nach aussen abzuschirmen und bei gleicher Amperewindungszahl die Flussdichte in dem von der Spulenanordnung umschlossenen Raum und damit durch das Werkstück zu vergrößern.A location-dependent different flux density can also be generated by means of a ferromagnetic yoke surrounding the coil arrangement outside. By appropriate design of the geometry of the yoke along the straight, long coil sides, the strength of the magnetic field along the axis of rotation can be influenced. The yoke also has the advantage of shielding the magnetic field of the coil assembly to the outside and the same Amperewindungszahl to increase the flux density in the space enclosed by the coil arrangement and thus by the workpiece.
Zur weiteren Erhöhung der Flussdichte kann das Joch ähn- lieh einem innenseitig offenen Torus ausgebildet sein.To further increase the flux density, the yoke may be similar to a torus open on the inside.
Stattdessen kann das Joch auch einen geschlossenen oder offenen Ring- oder C-Querschnitt mit mindestens je einem Polschuh beidseits der Drehachse haben. Im Fall eines of- fenen Querschnitts (rechtwinklig zur Drehachse) , genauer gesagt z.B. eines längs einer Mantellinie offenen Hohlzy- linders, liegt die Drehachse des Werkstücks zwischen den die schlitzförmige Öffnung begrenzenden und die Polschuhe bildenden bzw. als Polschuhe ausgestalteten Flächen des Hohlzylinders .Instead, the yoke may also have a closed or open ring or C-section with at least one pole piece on each side of the axis of rotation. In the case of an open cross-section (at right angles to the axis of rotation), more precisely e.g. a hollow cylinder which is open along a surface line, the axis of rotation of the workpiece lies between the surfaces of the hollow cylinder defining the slot-shaped opening and forming the pole shoes or designed as pole shoes.
Grundsätzlich kann die Spulenanordnung auf dem Joch an einer beliebigen Stelle sitzen. Das Magnetfeld kann jedoch auch mittels je einer supraleitenden Spule auf jedem PoI- schuh als Spulenanordnung erzeugt werden.In principle, the coil arrangement can sit on the yoke at any desired location. However, the magnetic field can also be generated by means of a respective superconducting coil on each shoe as a coil arrangement.
Die längs der Drehachse unterschiedliche Flussdichte kann auch durch einen sich längs der Drehachse ändernden Abstand der Polflächen der Polschuhe des Jochs erzeugt wer- den .The flux density which differs along the axis of rotation can also be generated by a spacing of the pole faces of the pole shoes of the yoke which changes along the axis of rotation.
Eine längs der Drehachse unterschiedliche Flussdichte des das Werkstück durchsetzenden Magnetfeldes kann insbesondere auch durch Änderung des von der Drehachse des Werk- Stücks und der Hauptachse des Magnetfeldes eingeschlossenen Winkels eingestellt werden. Dieser Winkel weicht dann von 90° ab. Der Punkt, um den die Drehachse gegen die Hauptachse des Magnetfeldes verkippt wird, kann in Abhängigkeit von der über die Länge des Werkstücks geforderten Temperaturverteilung gewählt werden. Wird die Drehachse beispielsweise um einen im Bereich einer Stirnfläche eines zylindrischen Werkstücks liegenden Punkt verkippt, so ver- bleibt dieser Bereich des Werkstücks im Bereich des starken Magnetfeldes, während der gegenüberliegende Stirnflächenbereich sich in einem schwächeren Magnetfeld befindet und daher weniger stark erwärmt wird. Der Verkippungs- winkel kann zwischen ca. 2° und ca. 20° liegen, entsprechend einem von der Drehachse und der Hauptachse des Magnetfeldes eingeschlossenen Winkel zwischen etwa 88° und 70°.A flux density of the magnetic field passing through the workpiece along the axis of rotation can in particular also be adjusted by changing the angle enclosed by the axis of rotation of the workpiece and the main axis of the magnetic field. This angle then deviates from 90 °. The point at which the axis of rotation is tilted against the main axis of the magnetic field can be selected as a function of the temperature distribution required over the length of the workpiece. If, for example, the axis of rotation is tilted about a point lying in the region of an end face of a cylindrical workpiece, then This area of the workpiece remains in the area of the strong magnetic field, while the opposite end area is in a weaker magnetic field and therefore less heated. The tilt angle may be between about 2 ° and about 20 °, corresponding to an angle between about 88 ° and 70 ° included by the axis of rotation and the major axis of the magnetic field.
Ausführungsmöglichkeiten des Verfahrens nach der Erfindung und schematisch vereinfachte Anordnungen zu dessen Durchführung werden nachfolgend an Hand der Zeichnung beispielhaft erläutert . Es zeigt :Embodiments of the method according to the invention and schematically simplified arrangements for its implementation will be explained by way of example with reference to the drawings. It shows :
Fig. 1 eine supraleitende race-track-Spule mit einem magnetischen Kurzschluss in einer Aufsicht und einer Seitenansicht,1 shows a superconducting race-track coil with a magnetic short circuit in a plan view and a side view,
Fig. 2 die gleiche Spule, jedoch mit einer parallelach- sig versetzten Zusatzspule,2 shows the same coil, but with a parallel offset additional coil,
Fig. 3 die gleiche Spule, jedoch mit einer wechselstromgespeisten Zusatzspule,3 shows the same coil, but with an AC-powered auxiliary coil,
Fig. 4 die gleiche Spule, jedoch mit zusätzlichem, einen Spulenschenkel umschließendem Joch,4 shows the same coil, but with an additional, a coil leg enclosing yoke,
Fig. 5 einen Querschnitt durch die supraleitende Spule mit umgebendem Joch,5 shows a cross section through the superconducting coil with surrounding yoke,
Fig. 6a eine andere Ausführungsform einer supraleitenden Spulenanordnung mit Joch in einer Stirnansicht und einer teilweise geschnittenen Seitenansicht,6a another embodiment of a superconducting coil arrangement with yoke in an end view and a partially sectioned side view,
Fig. 6b die gleiche Spulenanordnung wie in Fig. 6a, jedoch mit verkippter Drehachse des Werkstücks, Fig. 7a eine supraleitende Spule auf einem Schenkel eines C-förmigen Jochs in einer Stirnansicht und einer teilweise geschnittenen und um 90° gedrehten Aufsicht6b, the same coil arrangement as in Fig. 6a, but with tilted axis of rotation of the workpiece, Fig. 7a, a superconducting coil on a leg of a C-shaped yoke in an end view and a partially cut and rotated by 90 ° view
Fig. 7b eine Stirnansicht eines C-förmigen Jochs mit einer Anordnung aus zwei supraleitenden Spulen,7b is an end view of a C-shaped yoke with an arrangement of two superconducting coils,
Fig. 8a eine race-track-Spule ähnlich Fig. 1, jedoch mit verkippter Drehachse des Werkstücks,8a shows a race-track coil similar to FIG. 1, but with the axis of rotation of the workpiece tilted, FIG.
Fig. 8b eine Anordnung aus zwei gleichachsigen, supraleitenden Spulen im Schnitt,8b shows an arrangement of two equiaxed, superconducting coils in section,
Fig. 9 eine race-track-Spule wie in Fig. 1, jedoch mit im Spuleninnenraum linear längs seiner Drehachse verschobenem Werkstück,9 shows a race-track coil as in FIG. 1, but with a workpiece displaced linearly along its axis of rotation in the coil interior, FIG.
Fig. 10a ein Werkstück mit Temperaturmesspunkten,10a shows a workpiece with temperature measuring points,
Fig. 10b das gleiche Werkstück mit um 6° gegenüber einer zur Achse eines Magnetfeldes ortogonalen Achse verkippter Drehachse,10b shows the same workpiece with an axis of rotation tilted by 6 ° with respect to an axis orthogonal to the axis of a magnetic field,
Fig. 11 eine vereinfachte, jedoch perspektivische Darstellung eines zylindrischen Werkstücks, dessen Längs- und Drehachse gegenüber der Ebene einer umgehenden race-track-Spule verkippt ist.Fig. 11 is a simplified, but perspective view of a cylindrical workpiece whose longitudinal and rotational axis is tilted relative to the plane of an immediate race-track coil.
Fig. 1 zeigt eine supraleitende race-track-Spule S in schematischer Vereinfachung. Sie umfasst eine Anzahl von nicht dargestellten Windungen und ist gleichstromdurch- flossen, so dass sie ein Dipolmagnetfeld erzeugt. Dieses durchsetzt ein zylindrisches Werkstück W aus einem elek- trisch leitenden Werkstoff. Das Werkstück kann z.B. ein Aluminiumbarren oder -billet sein. Das Werkstück W ist um seine Längsachse D drehangetrieben. Der Antrieb ist nicht dargestellt. Auf diese Weise wird das Werkstück W, wie bekannt, induktiv erwärmt. Um längs des Werkstückes einen Temperaturgradienten zu erzeugen, befindet sich in dem oberen Teil des ovalen Raumes ein magnetischer Kurzschluss K, hier in Form eines kurzen Zylinders aus einem ferromag- netischen Werkstoff. In der Nähe dieses Kurzschlusses K wird das das Werkstück W durchsetzende Magnetfeld B geschwächt . Der obere Endbereich des Werkstücks W erfährt deshalb eine geringere Erwärmung als diejenigen Bereiche des Werkstücks, die von dem ungeschwächten Magnetfeld der Spule S durchsetzt werden.Fig. 1 shows a superconducting race-track coil S in a schematic simplification. It includes a number of turns, not shown, and is DC-flowed to produce a dipole magnetic field. This penetrates a cylindrical workpiece W made of an electrically conductive material. The workpiece may be, for example, an aluminum ingot or billet. The workpiece W is rotationally driven about its longitudinal axis D. The drive is not shown. In this way, the workpiece W, as known, is heated inductively. In order to generate a temperature gradient along the workpiece, a magnetic short circuit K is located in the upper part of the oval space, here in the form of a short cylinder made of a ferromagnetic material. In the vicinity of this short circuit K, the magnetic field B passing through the workpiece W is weakened. The upper end region of the workpiece W therefore experiences less heating than those regions of the workpiece which are penetrated by the unattenuated magnetic field of the coil S.
Fig. 2 zeigt die prinzipiell gleiche Anordnung wie Fig. 1, jedoch ist parallelachsig versetzt zu der Spule S eine Zusatzspule Z angeordnet, deren Windungen ebenfalls gleichstromdurchflossen sind. Bei gleichem Wicklungssinn der Zusatzspule Z und der Spule S überlagern sich die Magnetfelder im Sinne einer Verstärkung des den oberen Teil des Werkstückes W durchsetzenden Gesamtmagnetfeldes. Dieser Teil des Werkstückes W wird deshalb stärker als der übrige Teil erwärmt. Soll ein anderer Bereich des Werkstückes W stärker als die übrigen Bereiche erwärmt werden, so wird die Zusatzspule Z in Richtung des Doppelpfeiles an die gewünschte Stelle verschoben. Die gewünschte Tempera- turdifferenz oder Temperaturüberhöhung kann durch Veränderung des Erregerstromes der Zusatzspule Z eingestellt werden.Fig. 2 shows the principle the same arrangement as Fig. 1, but is offset parallel axis offset from the coil S, an additional coil Z is arranged, whose turns are also flowed through DC. With the same winding sense of the additional coil Z and the coil S, the magnetic fields in the sense of a reinforcement of the upper part of the workpiece W passing through total magnetic field overlap. This part of the workpiece W is therefore heated more than the rest of the part. If another area of the workpiece W is to be heated more strongly than the remaining areas, then the additional coil Z is displaced in the direction of the double arrow to the desired location. The desired temperature difference or temperature increase can be set by changing the excitation current of the additional coil Z.
Gemäß Fig. 3 wird der gleiche Effekt durch eine Wechsel- stromgespeiste Zusatzspule Zl erreicht, die in dem von der Spule S umschlossenen Raum und das Werkstück W konzentrisch umgebend sowie längs des Doppelpfeiles verschiebbar angeordnet ist .According to FIG. 3, the same effect is achieved by an additional current-fed auxiliary coil Zl, which is arranged concentrically in the space enclosed by the coil S and the workpiece W and displaceable along the double arrow.
Statt wie in Fig. 1 lediglich einen magnetischen Kurzschluss in dem von der Spule S umschlossenen Raum vorzusehen, kann gemäß Fig. 4 ein geschlossenes Joch J um den oberen kurzen Schenkel der Spule S angeordnet sein. Das Joch J verbessert den magnetischen Kurzschluss und schirmt gleichzeitig das Magnetfeld der Spule S an dieser Stelle nach außen ab. Auch in dieser Ausführung wird dementspre- chend der obere Bereich des Werkstückes W geringer erwärmt als der übrige Bereich.Instead of providing only a magnetic short circuit in the space enclosed by the coil S, as in FIG. 1, a closed yoke J can, as shown in FIG be arranged upper short leg of the coil S. The yoke J improves the magnetic short circuit and simultaneously shields the magnetic field of the coil S at this point to the outside. Accordingly, in this embodiment as well, the upper region of the workpiece W is heated less than the remaining region.
Eine Abwandlung dieser Ausführung ist durch Fig. 5 veranschaulicht. Ein Joch Jl umschließt die gesamte Spulenan- Ordnung und schirmt damit das Magnetfeld insgesamt nach außen weitgehend ab. Gleichzeitig verringert sich die zur Erzeugung des Magnetfeldes mit der Flussrichtung B benötigte Erregerleistung, genauer gesagt der Erregerstrom durch die Spule S. Die unterschiedliche Erwärmung des Werkstückes W, d.h. ein Temperaturgradient längs dessen Achse, kann auch in dieser Anorndung mit den anhand der Figuren 1 bis 3 erläuterten Maßnahmen erzielt werden.A modification of this embodiment is illustrated by FIG. A yoke Jl surrounds the entire Spulenan- order and thus largely shields the magnetic field to the outside. At the same time, the excitation power needed to generate the magnetic field with the flow direction B decreases, more specifically the excitation current through the coil S. The differential heating of the workpiece W, i. a temperature gradient along its axis, can also be achieved in this Anorndung with the explained with reference to Figures 1 to 3 measures.
Die in Fig. 6a dargestellte Anordnung geht von einem ge- schlossenen Joch J2 mit Polschuhen Pl und P2 aus, von denen jeder eine supraleitende Spule Sl bzw. S2 trägt, die elektrisch in Reihe geschaltet und gleichstromdurchflossen sind. Die unterschiedliche Stärke des Magnetfeldes ist durch die Strichstärke der die Feldlinien symbolisierenden Pfeile angedeutet. Wie die Seitenansicht verdeutlicht, kann durch mehr oder weniger weite Verschiebung des Werkstückes W längs seiner Drehachse D erreicht werden, dass ein Ende des Werkstückes W sich in dem zunehmend schwächer werdenden Streufeld außerhalb des Joches J2 dreht und dem- entsprechend schwächer als der übrige Bereich des Werkstückes W erwärmt wird.The arrangement shown in FIG. 6a is based on a closed yoke J2 with pole shoes P1 and P2, each of which carries a superconducting coil S1 or S2, which are electrically connected in series and through which DC flows. The different strength of the magnetic field is indicated by the line width of the arrows symbolizing the field lines. As the side view illustrates, can be achieved by more or less wide displacement of the workpiece W along its axis of rotation D that one end of the workpiece W rotates in the increasingly weakening stray field outside the yoke J2 and accordingly weaker than the rest of the area Workpiece W is heated.
Fig. 6b zeigt eine ähnliche Anordnung wie Fig. 6a, jedoch wird das Werkstück W in diesem Fall nicht durch Verschie- bung längs der Drehachse D sondern durch eine Verkippung dieser Drehachse gegenüber der langen Achse der Spulenanordnung Sl, S2, J erzielt. Dies ist durch die halbperspek- tivische Darstellung des zylindrischen Werkstückes W in der Stirnansicht der Fig. 6b angedeutet.FIG. 6b shows a similar arrangement to FIG. 6a, but in this case the workpiece W is not achieved by displacement along the axis of rotation D but by a tilting of this axis of rotation with respect to the long axis of the coil arrangement S1, S2, J. This is due to the semi-perspective shown in the end view of Fig. 6b.
Fig 7a zeigt eine Anordnung, bei der eine supraleitende Spule S3 den langen Schenkel eines C-förmigen Joches J3 umschließt, zwischen dessen Polschuhen P3 und P4 sich das Werkstück dreht. Die geschnittene und gedrehte Aufsicht verdeutlicht, dass die Polschuhe P3 und P4 einen sich keilförmig von rechts nach links verengenden Raum um das Werkstück W begrenzen, so dass das Werkstück W sich fortschreitend von rechts nach links entsprechend dem abnehmenden Luftspalt zunehmend stärker erwärmt . Diese Anordnung hat den Vorteil eines über die Länge des Werkstückes näherungsweise konstanten Temperaturgradienten.Fig. 7a shows an arrangement in which a superconducting coil S3 encloses the long leg of a C-shaped yoke J3, between which pole pieces P3 and P4 the workpiece rotates. The cut and rotated plan view illustrates that the pole shoes P3 and P4 delimit a space wedge-shaped from right to left around the workpiece W, so that the workpiece W progressively heats progressively from right to left in accordance with the decreasing air gap. This arrangement has the advantage of an over the length of the workpiece approximately constant temperature gradient.
Nach dem gleichen Prinzip arbeitet die Anordnung nach Fig. 7b, mit dem einzigen Unterschied, dass an Stelle einer Spule hier zwei supraleitende Spulen S4 und S5 eingesetzt werden, von denen jede einen Polschuh P5 und P6 umgibt.According to the same principle, the arrangement of FIG. 7b operates, with the only difference that instead of a coil here two superconducting coils S4 and S5 are used, each of which surrounds a pole piece P5 and P6.
Die in Fig. 8a dargestellte Anordnung arbeitet mit einer race-track-Spule S analog Fig. 1, jedoch wird die unterschiedliche Erwärmung des Werkstücks W längs seiner Drehachse D dadurch erzielt, dass diese Drehachse gegenüber der Mittelebene der Spule S um einen Winkel α um einen auf der Mittelachse M liegenden Punkt verkippt ist. Infolge dessen nimmt die Flussdichte B vom unteren zum oberen Ende des Werkstückes W ab, so dass das obere Ende des Werkstückes weniger stark als dessen übriger Bereich erwärmt wird.The arrangement shown in Fig. 8a operates with a race-track coil S analogous to FIG. 1, but the different heating of the workpiece W along its axis of rotation D is achieved in that this axis of rotation relative to the median plane of the coil S by an angle α to a point lying on the central axis M is tilted. As a result, the flux density B decreases from the lower to the upper end of the workpiece W, so that the upper end of the workpiece is heated less than the remaining portion thereof.
Nach dem gleichen Prinzip arbeitet die Anordnung nach Fig. 8b, jedoch mit zwei gleichachsig neben- bzw. hintereinander angeordneten, supraleitenden Spulen S6 und S7, wodurch eine höhere Flussdichte B erzielt wird.According to the same principle, the arrangement of FIG. 8b operates, however, with two coaxially adjacent or behind one another, superconducting coils S6 and S7, whereby a higher flux density B is achieved.
Auch Fig. 9 zeigt eine race-track-Spule S, die das Werk- stück W umschließt. Das Werkstück ist jedoch aus seiner symmetrischen Lage im von der Spule S umschlossenen Raum längs der Drehachse D nach oben verschoben. Infolge dessen liegt der obere Teil des Werkstückes W in einem Bereich höherer Flussdichte B als der übrige Bereich des Werkstückes, wird also stärker erwärmt. Analog der Anordnung in Fig. 8a kann das Werkstück gewünschtenfalls zusätzlich um einen dann zweckmäßig im Bereich der oberen Stirnfläche liegenden Punkt aus der Mittelebene der Spule S heraus verkippt werden (nicht dargestellt) .FIG. 9 also shows a race-track coil S which carries the work W encloses. However, the workpiece is shifted from its symmetrical position in the space enclosed by the coil S space along the axis of rotation D upwards. As a result, the upper part of the workpiece W is in a region of higher flux density B than the rest of the workpiece, so it is heated more. Analogously to the arrangement in FIG. 8a, the workpiece can, if desired, additionally be tilted out of the median plane of the coil S by a point expediently located in the region of the upper end face (not shown).
Die nachfolgende Tabelle veranschaulichen an einem numerischen Beispiel die erzielbaren Temperaturen und Temperaturunterschiede. Das Werkstück besteht aus einem Billet mit einer Länge von 800mm und einem Durchmesser von 250mm. In der Tabelle ist mit "Ausgleich" eine Wartezeit nach Beendigung der induktiven Erwärmung und vor Ermittlung der Temperaturen an den in Fig. 10a eingezeichneten Punkten bezeichnet. Der Verkippungswinkel o; in der ersten Spalte ist wie in Fig. 8a und 10b definiert. Die Linearverschiebung in der zweiten Spalte bezieht sich auf die an Hand von Fig. 9 erläuterte Verschiebung längs der Drehachse D des Werkstückes. Insbesondere die Einträge in den letzten fünf Zeilen zeigen, dass es vorteilhaft sein kann, die beiden grundsätzlich getrennt anwendbaren Maßnahmen der Verschiebung des Werkstückes und der Verkippung dessen Drehachse auch kombiniert anzuwenden. The following table illustrates on a numerical example the achievable temperatures and temperature differences. The workpiece consists of a billet with a length of 800mm and a diameter of 250mm. In the table, "compensation" denotes a waiting time after completion of the inductive heating and before determination of the temperatures at the points shown in FIG. 10a. The tilt angle o; in the first column is defined as in Figs. 8a and 10b. The linear displacement in the second column refers to the displacement along the axis of rotation D of the workpiece explained with reference to FIG. 9. In particular, the entries in the last five lines show that it may be advantageous to apply the two fundamentally separately applicable measures of displacement of the workpiece and the tilting of the axis of rotation combined.
Billet Spule TemperaturBillet coil temperature
Linearverschiebung i- α aus Mitte Länge Drehzahl Ausgleich a b C dLinear displacement i- α off center Length Speed Compensation a b C d
Pl [mm] [mm] [Hz] [S] [°C1 [0C] PCi PC]Pl [mm] [mm] [Hz] [S] [° C1 [ 0 C] PCi PC]
0 0 1500 4 50 350 350 380 4050 0 1500 4 50 350 350 380 405
2 O 1500 4 50 355 360 385 4202 O 1500 4 50 355 360 385 420
3 0 1500 4 50 360 350 385 4153 0 1500 4 50 360 350 385 415
5 0 1500 4 50 350 305 360 3935 0 1500 4 50 350 305 360 393
6 0 1500 4 50 350 280 340 3666 0 1500 4 50 350 280 340 366
10 0 1500 4 50 312 200 255 28410 0 1500 4 50 312 200 255 284
6 0 1500 4 50 350 280 340 3666 0 1500 4 50 350 280 340 366
6 0 1500 5 50 445 360 420 4606 0 1500 5 50 445 360 420 460
6 0 1500 6 50 550 435 500 5506 0 1500 6 50 550 435 500 550
6 0 1500 5 150 460 375 430 4406 0 1500 5 150 460 375 430 440
6 0 1500 6 150 545 445 495 5056 0 1500 6 150 545 445 495 505
0 0 1500 5 150 470 470 475 4900 0 1500 5 150 470 470 475 490
0 0 1500 5 150 470 470 475 4900 0 1500 5 150 470 470 475 490
6 0 1500 5 150 470 375 430 4406 0 1500 5 150 470 375 430 440
6 -50 1500 5 150 480 370 430 4456 -50 1500 5 150 480 370 430 445
6 -100 1500 5 150 490 370 440 4406 -100 1500 5 150 490 370 440 440
6 -200 1500 5 150 535 370 450 4506 -200 1500 5 150 535 370 450 450
Fig 11 veranschaulicht perspektivisch jedoch schematisch vereinfacht ein Billet mit verkippter Drehachse in einer race-track-Spule . Figure 11 illustrates in perspective but schematically simplified a billet with tilted axis of rotation in a race-track coil.

Claims

Patentansprüche claims
1. Verfahren zum induktiven Erwärmen eines elektrischleitenden Werkstückes durch Drehen des Werkstückes im Magnetfeld einer supraleitende Windungen umfassenden, gleichstromdurchflossenen Spulenanordnung um eine Drehachse, die mit der Hauptachse des Magnetfeldes einen Winkel einschließt, wobei die Flussdichte des das Werkstück durchsetzenden Magnetfeldes längs der Drehachse unterschiedlich eingestellt wird, dadurch gekennzeichnet, dass die längs der Drehachse unter- schiedliche Flussdichte mittels eines magnetischen Kurzschlusses in einem Teilbereich des Magnetfeldes erzeugt wird.A method of inductively heating an electrically conductive workpiece by rotating the workpiece in the magnetic field of a superconducting coil comprising DC coil assembly about an axis of rotation including an angle with the major axis of the magnetic field, the flux density of the magnetic field passing through the workpiece being adjusted differently along the axis of rotation , characterized in that the different flux density along the axis of rotation is generated by means of a magnetic short circuit in a partial region of the magnetic field.
2. Verfahren zum induktiven Erwärmen eine elektrisch leitenden Werkstückes durch Drehen des Werkstückes im Magnetfeld einer supraleitende Windungen umfassenden, gleichstromdurchflossenen Spulenanordnung um eine Drehachse, die mit der Hauptachse des Magnetfeldes einen Winkel einschließt, wobei die Flussdichte des das Werkstück durchsetzenden Magnetfeldes längs der Drehachse unterschiedlich eingestellt wird, dadurch gekennzeichnet, dass die längs der Drehachse unterschiedliche Flussdichte mittels einer Zusatzspule erzeugt wird.2. A method for inductively heating an electrically conductive workpiece by rotating the workpiece in the magnetic field of a superconducting windings, co-current through a coil assembly about an axis of rotation, which forms an angle with the major axis of the magnetic field, wherein the flux density of the workpiece passing through the magnetic field along the axis of rotation set differently is, characterized in that the different flux density along the axis of rotation is generated by means of an additional coil.
3. Verfahren zum induktiven Erwärmen eines elektrischleitenden Werkstückes durch Drehen des Werkstückes im Magnetfeld einer supraleitende Windungen umfassenden, gleichstromdurchflossenen Spulenanordnung um eine Drehachse, die mit der Hauptachse des Magnetfeldes einen Winkel einschließt, wobei die Flussdichte des das Werkstück durchsetzenden Magnetfeldes längs der Drehachse unterschiedlich eingestellt wird, dadurch gekennzeichnet/ dass die längs der Drehachse unterschiedliche Flussdichte mittels eines die Spulenanordnung aussen umgebenden ferromagnetisehen Jochs erzeugt wird.3. A method for inductive heating of an electrically conductive workpiece by rotating the workpiece in the magnetic field of a superconducting windings, co-current through a coil assembly about an axis of rotation, which forms an angle with the major axis of the magnetic field, wherein the flux density of the workpiece passing through the magnetic field along the Rotary axis is set differently, characterized in that the longitudinal axis of rotation different flux density is generated by means of a coil arrangement outside the surrounding ferromagnetic yoke.
4. Verfahren zum induktiven Erwärmen eines elektrischleitenden Werkstückes durch Drehen des Werkstückes im Magnetfeld einer supraleitende Windungen umfassenden, gleichstromdurchflossenen Spulenanordnung um eine Drehachse, die mit der Hauptachse des Magnetfeldes einen Winkel einschließt, wobei die Flussdichte des das Werkstück durchsetzenden Magnetfeldes längs der Drehachse unterschiedlich eingestellt wird, dadurch gekennzeichnet, dass die längs der Drehachse unterschiedliche Flussdichte durch Änderung des von der Drehachse und der Hauptachse des Magnetfeldes eingeschlossenen Winkels eingestellt wird.4. A method of inductively heating an electrically conductive workpiece by rotating the workpiece in the magnetic field of a superconducting coil comprising a DC coil assembly about an axis of rotation which forms an angle with the major axis of the magnetic field, the flux density of the workpiece passing magnetic field being adjusted differently along the axis of rotation , characterized in that the flux density different along the rotation axis is adjusted by changing the angle enclosed by the rotation axis and the major axis of the magnetic field.
5. Verfahren nach Anspruch 2, dadurch gekennzeichnet, dass die Zusatzspule parallelachsig versetzt zu der Spulenanordnung positioniert wird.5. The method according to claim 2, characterized in that the additional coil is positioned parallel axis offset from the coil assembly.
6. Verfahren nach Anspruch 2, dadurch gekennzeichnet, dass die Zusatzspule gleichaachsig zu der Drehachse und das Werkstück konzentrisch umgebend in einem Teilbereich des Magnetfeldes positioniert wird.6. The method according to claim 2, characterized in that the additional coil is positioned gleichaachsig to the axis of rotation and the workpiece concentrically surrounding in a partial region of the magnetic field.
7. Verfahren nach Anspruch 3, dadurch gekennzeichnet, dass das Joch ähnlich einem innenseitig offenen Torus ausgebildet ist .7. The method according to claim 3, characterized in that the yoke is formed similar to an inside open torus.
8. Verfahren nach Anspruch 3, dadurch gekennzeichnet, dass ein Joch mit einem offenen oder geschlossenen, Ring- oder C-Querschnitt mit mindestens je einem PoI- schuh beidseits der Drehachse verwendet wird. 8. The method according to claim 3, characterized in that a yoke is used with an open or closed, ring or C-section with at least one PoI- shoe on both sides of the axis of rotation.
9. Verfahren nach Anspruch 8, dadurch gekennzeichnet, dass das Magnetfeld mittels je einer supraleitenden Spule auf jedem Polschuh als Spulenanordnung erzeugt wird.9. The method according to claim 8, characterized in that the magnetic field is generated by means of a respective superconducting coil on each pole piece as a coil arrangement.
10. Verfahren nach Anspruch 8 oder 9, dadurch gekennzeichnet, dass die längs der Drehachse unterschiedliche Flussdichte durch einen sich längs der Drehachse ändernden Abstand der Polflächen der Polschuhe erzeugt wird.10. The method according to claim 8 or 9, characterized in that the longitudinal axis of rotation different flux density is generated by changing along the axis of rotation distance of the pole faces of the pole pieces.
11. Verfahren nach Anspruch 4, dadurch gekennzeichnet, dass der von der Drehachse und der Hauptachse des Magnetfeldes eingeschlossene Winkel auf einen Wert zwischen ca. 70° und ca. 88° eingestellt wird. 11. The method according to claim 4, characterized in that the angle enclosed by the axis of rotation and the main axis of the magnetic field angle is set to a value between about 70 ° and about 88 °.
EP06849391A 2005-12-22 2006-12-21 Method for inductive heating of a workpiece Withdrawn EP1847157A1 (en)

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Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102007034970B4 (en) * 2007-07-26 2010-05-12 Zenergy Power Gmbh Method and device for inductive heating of at least one billet
DE102007051144B4 (en) 2007-07-26 2010-06-02 Zenergy Power Gmbh Induction heater and method for adjusting the width of the wells of such induction heater
DE102007051108B4 (en) * 2007-10-24 2010-07-15 Zenergy Power Gmbh Method for inductively heating a metallic workpiece
KR101387492B1 (en) * 2007-11-26 2014-04-22 삼성전자주식회사 A heating unit, a reflow apparatus and a reflow method
FI20095213A0 (en) 2009-03-04 2009-03-04 Prizztech Oy Method and apparatus for induction heating
DE102010053283A1 (en) * 2010-12-02 2012-06-06 Zenergy Power Gmbh Method and induction heater for heating billets
DE102010053284A1 (en) * 2010-12-02 2012-06-06 Zenergy Power Gmbh Method and induction heater for heating a billet
US10232105B2 (en) 2011-03-28 2019-03-19 Biosurfit, S.A. Multi-chamber microfluidic device
CN103313449B (en) * 2013-05-14 2015-09-09 上海超导科技股份有限公司 Induction heating equipment and induction heating method thereof
CN103391654A (en) * 2013-06-28 2013-11-13 苏州科睿特能源科技有限公司 Device capable of realizing gradient heating of solid metal material
WO2015075661A1 (en) * 2013-11-22 2015-05-28 NDLOVU, Raymond Device for controlling the pressure in a vehicle tyre
US10525470B2 (en) 2016-06-09 2020-01-07 Biosurfit, S.A. Liquid flow control
KR101877118B1 (en) * 2016-06-14 2018-07-10 창원대학교 산학협력단 Superconducting dc induction heating apparatus using magnetic field displacement
CN118971555B (en) * 2024-10-14 2025-03-25 西安聚能超导磁体科技有限公司 A superconducting motor device for induction heating

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1111279A (en) * 1965-10-06 1968-04-24 Deutsche Edelstahlwerke Ag An arrangement for continuously locally varying the specific heating effect of and inductor

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1036886B (en) * 1955-03-18 1958-08-21 Deutsche Edelstahlwerke Ag Device for inductive hardening of elongated workpieces
US2902572A (en) * 1957-03-05 1959-09-01 Penn Induction Company Induction heating of metal strip
CH568661A5 (en) * 1973-09-24 1975-10-31 Varta Batterie
US4761527A (en) * 1985-10-04 1988-08-02 Mohr Glenn R Magnetic flux induction heating
US4856097A (en) * 1988-03-29 1989-08-08 Glenn Mohr Apparatus for induction heating of electrically conductive metal wire and strip
US5032748A (en) * 1988-11-11 1991-07-16 Sumitomo Heavy Industries, Ltd. Superconducting DC machine
US5251685A (en) * 1992-08-05 1993-10-12 Inland Steel Company Apparatus and method for sidewall containment of molten metal with horizontal alternating magnetic fields
JPH08212512A (en) * 1995-02-03 1996-08-20 Hitachi Ltd Magnetic storage device, thin-film magnetic head used therefor, and manufacturing method thereof
US6942469B2 (en) * 1997-06-26 2005-09-13 Crystal Investments, Inc. Solenoid cassette pump with servo controlled volume detection
US6208497B1 (en) * 1997-06-26 2001-03-27 Venture Scientifics, Llc System and method for servo control of nonlinear electromagnetic actuators
JP3582049B2 (en) * 1997-07-25 2004-10-27 スチールプランテック株式会社 Induction heating device
US6602620B1 (en) * 1998-12-28 2003-08-05 Kabushiki Kaisha Toshiba Magnetic recording apparatus, magnetic recording medium and manufacturing method thereof
DE20023192U1 (en) * 2000-07-26 2003-12-24 Schmidt, Arno Core-type induction furnace used for melting, heating and/or metallurgically treating metals uses magnetic field guided to inductor coil which penetrates melt and produces electromagnetic transformatory flow voltage
DE20203784U1 (en) * 2002-03-08 2003-07-24 Franz Haimer Maschinenbau KG, 86568 Hollenbach Device for inductively heating a tool holder
NO317391B1 (en) * 2003-01-24 2004-10-18 Sintef Energiforskning As Apparatus and method for induction heating of electrically conductive and non-magnetic material
DE102004021818A1 (en) * 2004-04-30 2005-12-08 Alpha Ip Verwertungsgesellschaft Mbh Energy-efficient heating plant for metals

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1111279A (en) * 1965-10-06 1968-04-24 Deutsche Edelstahlwerke Ag An arrangement for continuously locally varying the specific heating effect of and inductor

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
BAUSER M ET AL: "Passage", 1 January 2001, STRANGPRESSEN, ALUMINIUM-VERLAG DUESSELDORF, GERMANY, PAGE(S) 552 - 557, ISBN: 3-87017-249-5, XP008138131 *
MASSIMO FABBRI ET AL: "temperature distribution in aluminum billets heated by rotation in static magnetic field produced by superconducting magnets", COMPEL: THE INTERNATIONAL JOURNAL FOR COMPUTATION AND MATHEMATICS IN ELECTRICAL AND ELECTRONIC ENGINEERING, EMERALD GROUP PUBLISHING LTD, GB, vol. 24, no. 1, 1 January 2005 (2005-01-01), pages 281 - 290, XP008138135, ISSN: 0332-1649, DOI: 10.1108/03321640510571309 *
See also references of WO2007093213A1 *

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